• Korean Journal of Ecology and Environment
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• v.36 no.3 s.104
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• pp.257-268
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• 2003

Daily monitoring was conducted to elucidate the changes in turbidity and distribution of particles in the turbid water of a river-type reservoir (Paltang Reservoir) from 1999 to 2001. Water turbidity and the particle distribution of turbid water were principally affected by meteorological factors particularly rainfall patterns and hydrological factors such as inflow and outflow. The mean concentration of turbidity was constant each year, with the concentration of less than 10 NTU accounting for 85%. Seasonal characteristics were remarkable, with winter and spring having < 5 NTU, autumn 5 ${\sim}$ 10 NTU, and summer > 20 NTU. Unlike hydrological changes, maximum turbidity was observed from late July to early August and continuously increased from 1999 to 2001. In particular, the maximum turbidity of reservoirs remarkably increased toward the lower part of reservoir in 2001. Discharge and turbidity increased or decreased slowly in 1999; in contrast, turbidity rapidly increased in the early rainfall period of 2000 and 2001 but later decreased as discharge increased. In the particles of turbid water, clay ingredients were more densely distributed and more dominant in all stations. Of the total particles in turbid water, clay constituted 63.9${\sim}$66.6% and silt 33.4${\sim}$36.1% to account for a combined total of 98.9 ${\sim}$ 100%. Sand made up less than 1.1%. The turbidity of river-type reservoir was also found to be mainly affected by the biomass of plankton in a non-rainfall period. During a rainfall period, however, the quantity and relative ratio of inorganic particles depending on the soil components affected turbidity.

• Applied Microscopy
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• v.39 no.2
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• pp.125-132
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• 2009

Extracts and fractions of Inonotus obliquus (Chaga in Russia) have been known to have various biological activities, including antimutagenic, anticancer, antioxidative, and immunostimulating effects. This study was performed to confirm anticancer effect of 10% superfine Chaga mushroom processed by nano-mill technology on C57BL/6 mice. Chaga particles belonged in the size of 1 ${\mu}m$ was about 40% after nanomill processing according to the volume distribution. As the result of subcutaneous injection of B16BL6 melanoma cells to the mice, the tumor volume (p<0.001) and tumor weight (p<0.01) was significantly decreased in the experimental (NCh) group as compared with control (C) group and the tumor growth inhibitory rate was 29.2%. On examination of survival rate after intraperitoneal injection of B16BL6 melanoma cells, the mean survival time per a mouse was 17.7 and 26.0 days in C and NCh group respectively. The survival rate of NCh group was 40% when that of C group was 0% at the 35th day. On the result of examination to confirm histological toxicity by Chaga superfine particles, both groups did not show any morphological and pathological changes in the small and large intestine under the light microscope. These results suggest that feeding of superfine Chaga produced by nanomill technique has a tumor growth inhibitory effect in vivo.

• Korean Journal of Environment and Ecology
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• v.32 no.6
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• pp.591-602
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• 2018

Clithon retropictus has been designated as an endangered wildlife Class II due to its high value as a biological indicator species capable of judging environmental quality such as salinity, water flow, and ground conditions. However, basic research on its physiological and ecological characteristics is still lacking. As such, this study intended to examine the impact of environmental conditions such as salinity and soil particle size on the size and density of Clithon retropictus at the Yeoncho river estuary. The investigation of the salinity, which is a key variable that affects the distribution of organisms in the estuary, showed that Clithon retropictus could grow at a salinity ranging from 0#x2030; (freshwater) to 25‰ (brackish water). The coarse gravel (19-75mm) tended to increase nearer the upper stream (under the Yeoncho weir), while the proportion of particles smaller than sand (less than 19mm) increased toward the downstream. The population and the size of the individuals decreased rapidly in the downstream where water stagnated near the Yeoncho weir, and the salt water joined. The results indicated that Clithon retropictus had a high tolerance to salinity, but the adaptability was weaker toward the extremes since the population, and the size tended to decrease as the salinity increased. The correlation analysis revealed that both salinity and soil particle size affected the population and individual size. The correlation between the individual size and salinity was -0.242 (P <0.01), indicating that the size decreased with increasing salinity. The correlation between individual size and coarse gravel having a particle size of 19mm or more was 0.420 (P <0.01), indicating that the size increased with increasing the particle size.

• Journal of Forest and Environmental Science
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• v.17 no.1
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• pp.29-36
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• 2001

Compared to other industries, pulp and paper industry use a lot of water. As a result, a large amount of the waste water is discharged in the pulp and paper industry. This study was investigated to prevent the environmental pollution terribly faced with our society nowadays. In the waste water of pulp and paper, there are so many things in the waste water, like fiber, filler, and other organic solvent etc. so we must remove them from our environment. This study was investigated to experiment on test of impressed filtration with the kind and quantity of coagulant and the variance of pressure. In this study, we used feds, alums. $CaCl_2$, polymer as a coagulant and these pressure was 49, 98, 147, 196kpa. According to this study, we measured the speed of filtration and turbidity, measuring filtrated water. According to the values, we know the fact that as the consistency of coagulant and pressure were high, the filtration was good.

• Proceedings of the Korea Water Resources Association Conference
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• 2019.05a
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• pp.203-203
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• 2019

도시화로 인한 불투수면의 증가는 물순환 왜곡, 비점오염원 발생 및 수생태계 건상성 훼손 등을 야기시키며, 이를 해결하기 위하여 다양한 LID 기법을 적용하고 있다. 일반적으로 LID 내 적용 되는 여재들은 무기성여재로 중량이 크고 미세공극의 부재로 물리화학적 및 생물학적 저감기능이 제한적이다. 따라서 본 연구에서는 중량성이 낮은 생물폐자원을 선정하여 LID 시설 적용성평가를 수행하고자 한다. 생물폐자원은 발생량, 경량성 및 용이성을 고려하여 꼬막껍질(CS)과 호두껍질(WS)을 선정하였다. 생물폐자원의 산화부식을 고려하여 무기성 여재인 화산석과 혼합하여 Bioretention 시설에 적용하였으며, 여재 혼합비율에 따라 총 3가지의 Case 로 구성하였다. 식생은 구절초와 꽃댕강나무를 식재하였으며, 여재의 물리적 특성 분석을 위하여 적용 전과 후의 SEM(Scanning Electronic Microscope)을 수행하였다. 모니터링은 도로퇴적물 100g과 물 110L를 제조하여 인공강우유출수를 이용하여 수행하였으며, $0.0003{\sim}0.007m^3/sec$의 유속으로 주입하였다. 시설의 유입 및 유출부에서 유량 측정 및 수질 시료를 채취하였으며, 채취된 시료는 수질오염공정 시험법에 준하여 입자상 물질, 유기물, 영양물질 및 중금속 등을 분석하였다. Bioretention 시설의 모니터링 결과를 이용하여 물수지 및 TSS 저감 효율을 산정하였으며. 물수지 분석결과 시설의 저류율은 Case 1(soil) > Case 3(WS+RV) > Case 2(CS+RV) 순으로 나타났다. 시설 내 공극률이 가장 낮았던 Case 1에서 저류율이 약 55%로 가장 높게 것으로 분석되었다. Case 3(WS+RV)은 Case 2(WS+RV)와 시설 내 공극률이 유사함에도 불구하고 저류율이 약 10% 높은 것으로 분석되었다. 오염물질 저감효율 분석 결과, TSS와 TP의 제거효율은 모든 Case에서 약 75% 이상으로 높게 나타났으며, COD의 경우 모래를 적용한 Case 1에 비해 생물폐자원인 꼬막껍질과 호두껍질을 적용한 Case에서 약 1.3배 이상 높게 나타났다. 호두껍질과 꼬막껍질의 SEM 분석 결과 표면에 다공성이 형성되어 있는 것으로 조사되었다. 이는 여과 및 저류기작으로 인한 물순환 효과증대와 다공성과 돌기사이로 인한 입자상의 물질 여과 및 흡착으로 인하여 오염물질의 제거효율이 증대 된 것으로 평가된다. LID시설 내 생물폐자원과 무기성여재를 적절히 배합하여 복합여재로 조성할 경우 침하현상을 방지할 뿐만 아니라 저류 및 침투기능 향상과 미생물의 서식환경을 제공하기에 물순환 회복 및 비점오염물질 저감에 기여할 것으로 평가된다.

• Economic and Environmental Geology
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• v.39 no.6 s.181
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• pp.739-752
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• 2006

Deep-sea surface sediments acquired by multiple corer from 69 stations in the Clarion-Clipperton fracture zone of the northeast equatorial Pacific, were examined to understand the correlation of mass physical properties and sedimen-tological processes. The seabed of the middle part ($8-12^{\circ}N$) of the study area is mainly covered by biogenic siliceous sediment compared with pelagic red clays in the northern part ($16-17^{\circ}N$). In the southern part ($5-6^{\circ}N$), water depth is shallower than carbonate compensation depth (CCD). The mass physical properties such as grain size distribution, mean grain size, water content, specific grain density, wet bulk density, void ratio, and porosity of sediments are distinctly different among the three parts of the study area. Surface sediments in northern part are characterized by fine grain size and low water contents possibly due to low primary productivity and high detrital input. Conversely, sediments in the middle part are characterized by coarse grain size and high water contents, which might be caused by high surface productivity and deeper depth than CCD. The sediments show low water contents and high density in the southern part, which can be explained by shallower depth than CCD. Our results suggest that the variations in mass physical properties of sediments are influenced by combined effects including biogenic primary productivity of surface water, water depth, especially with respect to CCD, sedimentation rate, detrital input, and the geochemistry of the bottom water (for example, formation of authigenic clay minerals and dissolution of biogenic grains).

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.17 no.3
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• pp.189-201
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• 2012

Radiocarbon is a powerful tool for studies of carbon cycling in the ocean. Development of measurement technology of accelerator mass spectrometry has enabled researchers to measure radiocarbon even in specific compounds. In this paper, a brief introduction on radiocarbon measurement and reporting of radiocarbon data is provided. Researches that used radiocarbon measurements on bulk organic matter, organic compound classes, and specific organic compounds are reviewed. Examples include works to understand the cycling of particulate and dissolved organic matter, biochemical composition of particulate organic matter, post-depositional transport of sedimentary organic matter, selective incorporation of fresh organic matter by benthic organisms, chemoautotrophy by archaea, and sources of halogenated chemical compounds found in marine mammals.

• Proceedings of the Korean Vacuum Society Conference
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• 2013.02a
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• pp.258-258
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• 2013

최근 건조 제품의 양질화, 고급화 및 편의화가 요구되어 이를 충족시키기 위한 새로운 건조방법이 계속 개발 되어 왔다. 이러한 방법들 중에서 저온과 진공하에서 건조가 이루어지는 진공 동결 건조는 가장 완벽한 건조 방법으로 최근 실용화 되고 있다. 진공동결건조란 건조의 한 종류로 수분을 함유한 시료를 동결시킨 후 진공펌프를 이용하여 수증기압을 3중점 이하로 낮추어 얼음을 직접 증기로 만드는 승화의 원리에 의해서 얻어진다. 분무진공동결건조의 특징은 (1) 물리적구조의 보존성, (2) 화학적인 안정성, (3) 생물학적인 활동의 보존성, (4) 제품의 높은 복원성 및 재생성이다. 따라서 분무진공동결건조 기술은 크게 진공, 분무, 동결, 건조, 멸균 등과 같은 요소기술의 복합기술이라 할 수 있다. 분말을 제조하기 위해서 진공동결건조 후 분쇄하는 방법을 사용하나 본 방법에서는 정밀화학품 제조를 위해서 분무진공동결건조 방식을 사용한다. 이를 통하여 적당한 크기인 5~10 um의 입경 제조가 가능하고, 공기동력학적인 입경이 기존 방식에 비해 작아서 허파까지의 운반효율이 1.5~2배 우수하다. 화학, 의학 분야에서의 분무동결 건조는 주로 민감한 제품, 즉 생물학적 고유성의 손상 없이 물을 제거하는데 사용되어 영구적으로 저장 가능한 상태로 보관할 수 있으며 물의 첨가로 원상태로 복구할 수 있어서 매우 각광을 받고 있다. 의약용 냉동건조 제품은 항생물질, 박테리아, 혈청, 백신, 검사 약물, 단백질을 포함하는 생물공학 제품들, 세포, 섬유, 화학제품 등이 있으며 주로 vial 또는 ampule 상태로 건조가 이루어진다.본 연구에서는 원료를 $-194^{\circ}C$의 액체질소에 분무시켜 동결된 미립자를 형성한 후 진공 및 저온상태에서얼음의 승화(sublimation)에 기반한 1차 건조와 수증기 탈착(desorption)에 기초한 2차 건조 과정으로 구성된 분무진공동결건조기를 개발하였다. 분무동결 과정의 해석을 통해 2유체식 노즐을 통해 분무된 미세 입경의 액적이 액체 질소 표면까지 도달하는 회수률, 분무 노즐의 위치, 운전 조건 및 용기의 설계의 최적화를 수행하였다. 초기 액적속도, 분무노즐의 높이, 흡입구 추가에 따른 액적 유동 및 회수의 특성을 제시하였으며 이를 통한 분사시스템 고도화 가능성을 제시하였다. 구형의 미세 입자가 적층된 제품의 동결건조 공정의 해석은 흡착승화 모델(sorption sublimation model)을 기반으로 다음과 같은 열전달, 물질전달, 상변화 모델을 고려하여 유도되었다. 분무노즐 및 냉동/진공 배기계 시작품을 개발하여, 표면의 고다공도를 갖춘 입경 3~20 m 정도의 시료를 얻을 수 있으며, 동역학적 입경 5 m 충족함을 확인하였다.

• Journal of Korean Society of Environmental Engineers
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• v.31 no.10
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• pp.927-932
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• 2009

Toxic and recalcitrant organic pollutants in wastewaters can be effectively treated when advanced oxidation and biodegradation are combined, ideally with intimate coupling, in which both processes occur simultaneously in the same system. One means to achieve intimate coupling is to coat nanoscale $TiO_2$ on the outside of macroporous biofilm carriers. This study investigated the kinetics of photocatalysis with $TiO_2$-coated porous carriers. The carriers were made of polyvinyl alcohol (PVA) and coated with $TiO_2$ using a low-temperature sol-gel process. The $TiO_2$-coated carriers catalyzed the oxidation of methylene blue (MB) effectively under irradiation of UV light. The overall reaction rate with adsorption and photolysis saturated at high MB concentration, and approached the adsorption rate, which was first order for all MB concent rations. This result indicates that adsorbed MB may have slowed photocatalysis by blocking active sites for photocatalysis. The overall kinetics could be described by a quasi-Langmuir model. The estimated maximum specific (per unit mass of $TiO_2$) transformation rate of MB by the $TiO_2$-coated carriers was four times larger than that obtained from slurry-$TiO_2$ reactors. This observation demonstrated that the $TiO_2$ present as a coating on the carriers maintained high efficiency for transforming recalcitrant organic matter via photocatalysis. These findings serve as a foundation for advancement of an intimate coupling of photocatalysis to biodegradation.

• Journal of Conservation Science
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• v.33 no.4
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• pp.283-295
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• 2017

It is crucial to measure meteorological elements in relation to the biodeterioration of building cultural heritages. The Beopjusa and Seonamsa temples located respectively in Chungbuk and Jeonnam provinces, Korea, exhibit biological damage to the building cultural heritages and cause noticeable climatic differences. To compare biodeterioration environments of the abovementioned temples, 10 meteorological elements were observed, and particulate matter (TSP) was collected at each location. Furthermore, a correlation analysis was conducted between meteorological elements, and between meteorological elements and TSP. The local meteorology at Beopjusa temple characteristically showcased high total horizontal radiation, UV radiation, evaporation, wind speed, and TSP concentration, whereas, that at Seonamsa temple showcased high temperature, humidity, dew point temperature, air pressure, precipitation and number of days with precipitation. An elemental analysis of TSP revealed the presence of sae-salts at Seonamsa temple, and compared to that of Beopjusa temple, the monthly frequencies of biogenic aerosol and Fe-containing particles were higher. The correlation analysis showed that wind speed and humidity were major meteorological factors at Beopjusa and Seonamsa temples, respectively. Subsequently, the characteristics of the local meteorology at Seonamsa temple are expected to affect the biological damage of the building cultural heritages, which is favorable for the growth of various organisms.